SEWING MACHINE FOR DETECTING WORKPIECE THICKNESS

PROBLEM TO BE SOLVED: To provide a general-purpose sewing machine with a sensor which can secure an undisturbed operation method. SOLUTION: The sewing machine (1) with the sensor (34) for detecting the workpiece thickness (d1;d2) is provided with a substrate (2) including a bearing plate (23) for the workpiece (24;24, 25), a strut (3), which has an adjacent arm (4) including a head (5) and is formed to the bearing plate (23), a stitch forming part (21) having a sewing needle (11), and a feeding device (30) for feeding the workpiece (24;24, 25) in the feeding direction (31). The sensor is an ultrasonic sensor (34) which is arranged on the upstream side of the stitch forming part (21) and at a position above the bearing plate (23) in the feeding direction (30). It has a circuit (36) for transmitting a measured value, which corresponds to the workpiece (24;24, 25) thickness (d1;d2), to an electric control system (38). The control system (38) is connected to a unit (37), which is for transmitting the change command to at least one servo constituent element (15, 29) and/or a driving motor (9) of the sewing machine (1) depending on the detected thickness (d1;d2). COPYRIGHT: (C)2005,JPO&NCIPI